Detonating fuse



July 17, 1923- J. H. WOODBERRY DETONATING FUSE 2 sheets-sheet 1 Filed Dec. 10, 1918 July 17, 1923- J. H. WOODBERRY DETONATING FUS E Filed Dec. 10 1918 2 Sheets-Sheet 2 P x In 7 THHHWHMMWM.

"a citizen of the United States, stationed at Washington, District'of Columbia, have in- @ve'nted an Improvement in D-etonating Lei...

Patented July 17, 1923.

UN TED S TESMTPATENT QFFIC nn ronnrme' FUSE- v Application filed December 10,1918. Serial No. 266,144. I j

madman THE new or MARCH 3, 1883; 22 sum. 1., e25.

jTo'iaZl whom it ma concern: "Be'it known that JOHN H. WOODBERRY, major, Ordnance Dept, UnitedStates Army,

Fuses,'of which the following is aspecification.

I The invention described herein may' be used by the Goverment, or: any-of its'oflicers' or employees in prosecution of work for the Government, or by any other person in the United States, without payment of any'royexplosive elements usually primer, detonator and booster charge, all of alty thereon.

vide means for utilizing this safety means for holding separate the sensitive detonating elements from the booster charge until after the projectile leaves the gun. i a

Other objects and advantages will be apparent as the description proceeds. 1 1

The'accompanying drawings disclose zillustrative embodiments capable of carrying out the underlying principles of the-invention. Like reference characters indicate cor- "In fuses for high explosive projectiles, the

consists which are high explosives. In most fuses the arrangement is such that an explosion of the primer or detonator will produce an explosion of the booster and consequently the shell, and unless special safety means are provided for separating the detonator'from the booster, an accidental explosion of the shell may result, in storage, transportation or while it is in flight in the bore of the gun,

through a premature explosion of the detsitive nature.

onating elements which are of a highly sen- My invention is designedto provide safety means for separating the detonating ele-' ments from the booster elements by means hereinafter described.

It is well known to those skilled in the art that while the projectile is passing through the bore of the gun in flight the component parts are subjected to forces due to linear acceleration and angular velocity.

My invention resides in the utilization of a component part of the forces due to linear acceleration to overcome centrifugal force on a safety member included in the safety mechanism. I

The embodiments of my invention as illustrated inthe accompanying drawings show simple means for utilizing this principle for i in the art, other embodiments are apparent.

the purpose described, but to those skilled responding parts throughout the several views. The several figures of the drawing may be briefly described as follows i' Fig. 1 is acentral longitudinal vertical section of a fuse showing one embodiment of my invention. I l 4 Figs. 2 and 3 are transverse sectional views on the lines 22 and 3.,3, respectively. A Fig. '4 is a collective perspective detail view of two units of my composite safety locking device. I

comprises an'e ongated cylindrical casin 1,'

having a rear enlargement 1, and a use stock 2 screwed on to the said enlargement 1 as shown. The fuse stock isprovided with a rear extension 2 of reduced'diameter and screws into theshell casing A..- Secured in the rear open end of said extensionsis an elongated cup 10, the mouth thereof communicating with the chamber of the extension 2. The extension 2, and the cuplO-con- 'stitutes the booster casing.

The plunger 6 is mounted for rectilinear sliding movement in said fuse stock 2 and for this purpose is guided in its movements by an annular'fiange 2*- and by a flange 2 in the rear of flange 2; Between flanges 2* and 2 is an air-chamber 21, surrounding the plunger 6, which communicates through radial openings 22 in the fuse stock, with the outside atmosphere. v

The forward face ofthe flange 2 is inclined in a direction oblique to the axis of the plunger 6 and to the fuse stock 2, as shown at 17 and this oblique face constitutes 1' tension 2.

325 which carries the "I said extension by a shear pin '5.

a seat for safety lobking meinbers 16, 'inore particularly hereinafter to be described.

In front of the flang e 2 the fuse stock is provided with radial openings 2 by 5 which the air chamber 2 in front of said flange 2 may communicate with the outside atmosphere.

The plunger 6' is provided witha forward projecting hollow extension 6, and adja- 7' 0 cent/to the rear end of'said extension the .plunger 'is provided'withr a circumferential -agdooi're or recess 18, for a purpose presently appearing. The plunger :is also provided with a-iperipheral pocket 19, which,in the -45 normally "lockedposition of the plunger,

To render the fuse safe during transportation and storage, there is provided a loosexlockingcollar 11," which is, by a shear v'pin 12, held-rigidly onithe casing 1, adjacent to but spaced from the enlargement 1.

When the sleeve is in the normal T'positfion, as shown by Fig. 1, it bears on the spherical locking member 13 in the recess 14 of the extension 6 'andinan alined aperture 15 of the casing 1. This arrangement locks the plunger extension 6 to the fuse casing and i also binds the locking members 16' against "the oblique seat 17 and against the shoulder defining the "front terminus of thegroove '18,

preventing said members from becoming separated by a lateral shock during transvportation.

The zplunger 6-is permitted to move rearwardly to armed: osition only through the action of the loc ing members 16, which i do not move from the position'shown in Fig. 1,.upon firing, until linear acceleration of the projectile 'ceases. At this instant Tc which occurs shortly after the projectile leaves the bore, centrifugal force on these {members, beingino longer opposed, moves them outward, disengaging the plunger 6. I This. composite locking device is composed of a plurality of sectors (four being shown in thisinstance), havingan inclined face 16* which fits-theffrustro-conical surface 17 in the front face of-the flange-2 The shape "ofthese sectors is cle'arlyshown in Fig. 4,

and it will be noted that they are normally seated in the peripheral recess 18 and are arranged symmetricallyaroun'd' the plunger 6. Consequently, by the construction described, iI1,'OXCl8I to ;:release the plunger, the sectors must move radially and also axially forward.

The operation may be briefly described as "follows On firing the projectile the safety members 16,"while in the bore are subjected to forces due to linear acceleration and rotation. Diagrammatic representation of these forces is shown in Fig. 8, in which'o "isthe center'of gravity of one oft'he locking'members. The vector L, represents the force actingon thispart due to linear steam:

tion. Vector R represents thberitiiffigal force acting on this part. The vectors 8 and c represent respectivelythe com oii'en'ts of these forcesin a direction 'paralle' to the seat'on which the member is constrained to move. s 1.

In designing the fuse the angleof inclination A is so chosen thatthe'component s will always be greater than the component a while the projectileis traveling the bore. This condition therefore prevents outward mov ement .of the locking members; however, when the, projectile leavesthe bore ofthe gun the vector L ceases to exist'ja'nd "thecomponent 0 imparts an qutwaramtnon to the locking members 16. After th'elliicking members 16 li'ave'move'd outwardjsufficiently to disengageshoulder 6 the plunger 6 isfree to move rearward. Y

Air resistance on the head 8 of the'p lunger 6 now causes the plunger to move rearwardly to the dotted line position shown in Fig. 1, the movement beingflimited "by the shear pin 5 which contacts with the end of the casing 1. This movementtali'es the detonator 19 .from the safety chamber 21 through the firing pinfcu Where 'it i's in contact withthe booster charge. Upon'impact of the head 3 the; target, orthe like, the pin :5 is severed and :the plunger moves farther rearward, bringing the primer 7 into contact with the firing pin 8, thus exploding the detonatbr a, which detonates'the booster charge, iand c ause's the detonation of the main body of'thehighex plosive material. w

Before firing the fusethe detonatorj19 is surrounded byair-chamber 21 and'the' lower .part of this chamber is closed byjthefmetal end of plunger 6. Ii this position should the detonator 19 be accidentally exploded detonating wave will "not be transmitted to the booster charge'and therefore the shell will not'beexploded, since'the air-chamber serves to reduce the force of the explosion of thedeto'n'ator 19. Should itbe desirable to furth'er reduce the effects ofthe accidental explosion, vents'22'may beutilizedfor connec ting -the air-chambers 'with theatmosphere.

Fig. illustrates amodification of my de- -vice in which the centrifugal locking members 16 are shown used in connection with a standard time fuse rather than with a sensitive percussion operated fuse. This modifilinear acceleration and angular velocity may be utilized in fuses of various designs. This modification also shows a safety chamber 21' similar in its function to the safety chamber in Fig. 1. In this design the safety chamber is located within the shell and therefore it is necessary to incline the vent holes 22 corresponding with the vent hole 22 of Fig. 1. The reference character 12* represents a centrifugal lug for locking the plungerfi against the safety members 16*, thus preventing accidental displacement.

When the locking members 16 disengage the plunger 6* the fuseis armed. Upon the explosion of'the base charge of the time fuse either'by time action or impact, the

' plungerfi is driven violently rearward from 25 thes'afety position to the firing position and against the firing pin 8 This causes the detonation of the shell.

1 While]: have, in compliance with the letter'and spirit of the patent laws, described,

with great particularity, several specific structural embodiments of my invention capable of carrying out the underlying/prim ciples thereof, it is to be understood that various changes will suggest themselves to those skilled in the art to which the invention appertains, and that all of such modifications as come within the scope of the appended claims'constitute nodeparture from mv invention. i

Having thus fully described my invention, what I. claim as new, and desire to secure'by Letters Patent is 1. The combination with a fuse for pro jectiles, of a plunger detonator movable longitudinally of the fuse, a centrifugally movable locking member controlling the functioning of the fuse, said member lying on a surface oblique to the longitudinal axis of rotation of the projectile, the obliquity of said surface and the inertia of said member and of the plunger being effective to prevent the member from moving centrifugally during the acceleration period of the projectile in the bore of the gun.

2. The combination with a fuse for projectiles, of a plunger detonator moving from a non-functioning to a functioning position, a centrifugally movable locking device deterring the movement of said plunger to functioning position, said device lying on a surface oblique to the axis of rotation of the projectile, the obliquity of said surface and the inertia of said device and said plunger being efi'ective to prevent said device from moving centrifugally during the acceleraof the projectile and normally locked against movement by said plunger.

4. In a fuse for projectiles, the combination, with a plunger detonator having a recess providing an annular shoulder lying in a plane substantially at right angles to the longitudinal axis of the plunger, of safety means normally engaging said recess and contacted by said shoulder and moved in a direction oblique to the axis of said plunger to release the same.

5. In a fuse for projectiles, the combination, with a plunger detonator having a circumferential recess providing a shoulder lying in a plane substantially at right angles tothe longitudinal axis of the plunger, and

a composite safety device normally engaging Silldrecess and movable 1n a direction same, and an auxiliary locking device also.

normally engaging said plunger for preventing accidental release movement of said safety locking means.

7. In a fuse embodying a casing, a,1plun ger-detonator, .safety locking. mechanism normally engagcablc with said plunger-detonator to hold the same in unarmed relation, and centrifugally movable to releasing position, and a member normally locking said plunger-detonator to the fuse casing and preventing tendency to movement of said locking mechanism to releasing position, due to any lateral shock.

8. In a fuse embodying a casing a plunger detonator, safety locking mechanism. normally engageable with said plunger-detonator to hold the same in unarmed relation, and centrifugally movable to releasing position, and a member normally locking said pl1mger-detonator to the fuse casing and preventing tendency to movement of said locking mechanism to releasing position, due to any lateral shock, and means for maintaining the member against accidental displacement.

9. In a fuse embodying a casing, a plunger-detonator, safety locking mechanism normally engageable with said plunger-detonator to hold the same in unarmed relation, and centrifugally movable to releasing position, and a spherical body normally locking said plunger-detonator to the fuse casing and preventing tendency to movement of said locking mechanism to releasing position, due to any lateral shock, and a collar encircling said casing,'and bearing against said spherical body, for retaining the latter against accidental displacement.

10. In a fuse embodying a casing, a plungerdetonator, safety locking. mechanism normally engageable with said plunged-detonator to hold the same in unarmed rela tion, and centrifugally movable to releasing osition, and aspherical body normally lockmg said plunger-detonator to the fuse casing and preventing tendency to movement of said locking mechanism to releasing position, du'e'to any lateral sh'ock,and a collar encirclingsaid casing and bearing against said spherical body for retaining the latter against accidental displacement, and means for yieldingly retaining said collar against accidental displacement.

11. In a fuse embodying'a casing, a plungerdetonator, safety locking mechanism normally engageable with said plunger-detonator to hold the same" in unarmed relation, andcentrifugally movable to releasing position, and a body normally locking said plunger-detonator to the fuse casing and. preventing tendency to movement of said locking mechanism to releasing position, due to any lateral shock, and a collar encircling said casing and bearing against said bodytion and centrifugally movable to releasing position, means for locklng said p1ungerdetonator to the fuse casing and preventing tendencyto movement of said locking mechanism to releasing position, due to lateral shock imparted to the latter, and means for limiting the rearwardmovement of said plunger-detonator under impact therewith of air, when said locking m'eans' and said centrifugally operable locking means move to releasing position.

18. In a fuse embodying a casing, a plungerdetonator, safety locking mechanism normally engageable with said plunger-detonator to hold. the same/in unarmed relation and centrifugnlly movable torelasing position, means. for locking said plungerdetonator to the fuse casing and preventing a tendency to movement of said locking means to releasing position due to any lateral shock imparted to the latter, and a pin carried by said plunger-detonatorand impingible against said casing to limit rearward movement of said plunger under impact'therewith of air, when said locking means andsaid centrifugally operable locking means move to releasing position.

14. In a fuse, the combination with a fuse casing,-of afuse stock connected with said casing, a plunger detonator movable axially of said fuse stock, a forwardly extending projection carried by said plunger and projecting beyond the forward end of sa id fuse casing, locking means in said fuse' stock and normally engaging said plunger to maintain the same in the forward position in the said fuse stock, and separate locking means normally locking said plunger extension to said fuse casing and preventing accidental releasing movement of said locking mechanism. I i

JOHN H. WQODBERRY. 

